As 22 crew members still on board the Russian expedition ship Akademik Shokalskiy await freedom from the Antarctic pack ice, authorities are beginning to ponder the lessons of it becoming trapped.
With Shokalskiy's 52 passengers now safely on the Aurora Australis, the Australian Maritime Safety Authority said it had stood down the rescue operation involving Chinese ship Xue Long, which also remained stuck in the ice near Commonwealth Bay.
"Neither of the ships is requesting special assistance at this stage," John Young, AMSA general manager of emergency response, told reporters in a teleconference.
"So AMSA will remain in contact with the ships and monitor developments."
Mr Young said the authority would perform a post-incident debriefing on the rescue, but the main responsibility for an inquiry into the ship's predicament would fall with the Shokalskiy's flag state, Russia.
"I guess they will make their own decisions about whether they should do so," Mr Young said.
Normal pack ice break-out in the Commonwealth Bay region, due south of Hobart, has been blocked in recent years by the presence of super iceberg B9B.
Chris Turney, leader of the Spirit of Mawson expedition which was aboard Shokalskiy, said the ship became stuck when thick, multi-year pack ice swept out to sea.
The Australian Antarctic Division, which operates Aurora to resupply bases, declined to say whether it was advisable for a ship to enter the area, as the Shokalskiy did for several days before becoming stuck on Christmas Eve.
"I think it's principally a matter for ships' captains," said the division's acting director, Jason Mundy. "But it's certainly been a challenging operating environment in recent years."
AMSA said the Shokalskiy had stores and provisions for 74 people for many weeks, and its crew was well supplied to await an easing of the pack ice, which is yet to reach its peak summer melt.
"Since the passengers have been rescued and are aboard Aurora we are much less concerned about Shokalskiy with all those extra people on board," Mr Young said.
The authority commandeered the Australian and Chinese ships' services for the complex rescue under the international Safety Of Life At Sea convention.
Mr Young said that, apart from some incidental expenses paid by AMSA, the costs of the diversion of the ships to the rescue would broadly fall to their government owners, and perhaps to insurance.
For Aurora the expenses include fuel as well as supplying the 52 extra passengers aboard the ship for several weeks before they reach Hobart.
Mr Mundy said no calculation had been made yet of direct financial costs to the Australian Antarctic Division, but the main impact would be to the country's already tightly stretched summer polar program.
"It's fair to say the space our program has for further unexpected events is much diminished this year," Mr Mundy said. "We've got very limited wriggle room."
He said work programs on the Antarctic continent had been scheduled around the absence of Aurora, which was yet to unload 30 per cent of its cargo at Casey, several days' steaming from the rescue site.
"Some was scientific equipment relating to programs around Casey and we're currently looking at how we can best cover off on that, perhaps by flying it off," he said.
Mr Mundy said the Aurora had only 40 personnel aboard at the time of the rescue, and, with the capacity for 116 passengers, had plenty of space for the Shokalskiy group.